The topic for vol. 5 of THE VOICE - The Masters of ThinkPad Development is "case design". The Mechanical Design Division, which is in charge of case design, is at the core of the efforts resulting in the tough ThinkPad case. I wanted to hear more about the explanation of the efforts to overcome the limits in case design from vol. 5 and interviewed the two men on the cover.
- Masters. Do you think there has been a lot of progress since Lenovo Voice vol. 5 was published?
Ohtani: That is a good question. When I look back on it, yes I think there have been many things. Some models that represent new challenges include the T420, T520/W520 and X1. The LCD side case panel is a new hybrid type on the T420 and T520/W520 and the X1 uses Gorilla Glass.
- What is the new hybrid type?
Ohtani: As I explained in vol. 5, we have been using CFRP (Carbon Fiber Reinforced Plastic) sandwiched foam boards since the Z Series, but the T420 and T520/W520 use molded materials. The molded materials are a hybrid that is a unified molding of CFRP and GFRP (Glass Fiber Reinforced Plastic) and I think this is the first time that this has been tried in the industry.
Mizoguchi: It took almost a year to improve the design enough to reach the mass production level. It is necessary to join different materials effectively when molding and this took a lot of effort.
The reason that this is a hybrid is because in the antenna areas GFRP must be used because CFRP is a conductor. However the contraction rates of CFRP and GFRP plastics are different. This can lead to one side of the material curving and that does not result in enough strength in the joining of the CFRP and the GFRP. Our handling of the CFRP in mass-produced plates was different. After many innovations we were able to achieve CFRP for this molding process that was ready for mass production.
Ohtani: The term CFRP is used collectively, but there are actually many types. The materials used in the Z Series, and the X300 and T400s were light and thin but "the cost..." The goal this time was to use a magnesium alloy to make it lighter and improve costs. There should be a mechanical design with the optimal balance for each product and I think that the balance is improved over the previous generation in the T420 and T520/W520.
Oh, and the CFRP in the T420s no longer keeps me awake at night with "the cost". (LOL)
- What are the new challenges for the X1?
Mizoguchi: The Gorilla Glass of the X1 itself is very strong. It not only protects the glass surface of the LCD, but it actually contributes to increasing the overall rigidity of the case. The LCD side case panel is a thin magnesium alloy with slightly less strength than ordinary, but combining this with the Gorilla Glass offers more than sufficient strength. On the keyboard side, the same integrated high rigidity keyboard bezel ThinkPad roll cage is used from the X300 and T400s. I think that in the end, even though there is one more layer of glass, this has resulted in the first case design yet to maintain the necessary rigidity.
- There was something that surprised me when using the X1. The keyboard is highly rigid, but the typing feel is still very good. I pulled out the ThinkPad 600, which I thought was the top class design so far and compared them and I thought that the X1 was clearly better. I have an actual unit here...
Ohtani: (Compares typing on a 600 and an X1) Yeah, I think you are right. It is surprising how different it is. I think the 600 was pretty well known and the keyboard was very highly evaluated but there is real progress here with the X1.
Mizoguchi: A major reason that the rigidity of the keyboard has improved is because we are using an isolation (island) type keyboard. The unified keyboard frame between the keys is a solid design joined with the aluminum bottom plate chassis and this is one reason that the rigidity of the keyboard itself has been increased. Another reason is that we added hooks on both the left and right edges of the keyboard frame and matched this to the integrated keyboard bezel and ThinkPad roll cage. These two innovations were more effective than we expected.
- That makes sense. The design of this keyboard is excellent and is attracting a lot of attention, but aside from that, did you take other steps in mechanical design to contribute to the rigidity and typing feel?
Ohtani: That's right. The essence of "engineer spirit" is to set your heart on improving whatever new thing appears into something that has real value.
- Lastly I would like to hear your goals for the future.
Mizoguchi: I am working with Japanese carbon fiber manufacturers to develop a new CFRP. Our goal is to make something "about as strong as aluminum". Of course, it would also have to be as thin and light as aluminum or even thinner or lighter.
As I explained earlier, there are many types of CFRP. There are also grades of carbon fiber and there are already many that are very strong. The highest grade carbon fiber is used in fishing rods and is even better than the parts used in airplanes and F1 race cars. However, it is not suitable for mass production in notebook PCs. There are fishing rods that cost hundreds of thousands of yen and are almost works of art. Of course, it is necessary to consider the balance with the cost. There are still many issues to consider, but I think in the near future success is possible.
Ohtani: We will continue pursuing ThinkPad toughness as we always have, and I think this will also remain a core priority. However, I think the desire for "advantages including an attractive appearance" will be in increasing demand in the future. X1 and Edge were products designed with this in mind and I think there is a lot that Mechanical Design can do to contribute to this in the future.
For instance, the fibers of the current CFRP appear irregularly on the surface and the appearance of this is not attractive enough to be used in a product without painting. I think it would be great to develop a CFRP with an excellent appearance that would save both on the weight and the costs of the paint.
Mizoguchi: I would like to try some challenges in other areas including, "improving the drip-proof design of the keyboard bezel". I think the drip-proof design of the keyboard is the first in the industry, but if liquid enters through the aperture at the keyboard bezel, it currently can reach all the way to the motherboard. Liquid is not always only going to be spilled on the keyboard.
- I have high expectations for your "engineer spirit". Thank you very much.
Click here*Japanese only to access the full version of Lenovo Voice vol. 5 and other catalogs. THE VOICE –ndash; The Masters of ThinkPad Development The struggle for low weight and high rigidity at the cutting edge of case design